feat(gpu-service): scope create forms by the selected organization

In the platform-admin "all organizations" view, add an organization picker
(the CreateOrgScopeField slot) to the SSH public key, storage type,
storage, GPU instance and instance-template create forms, placed below the
name / display-name fields. Drop the hidden owner field and let the owner
derive from the request context, matching the model-route form.

For GPU instances, scope the instance-type list to clusters the chosen org
owns (client-side, by cluster owner) so an instance can't be scheduled onto
another org's cluster; when the org owns none, show "no instance type
available" and clear the selection, cluster and CPU/memory fields. Instance
templates gain a Global level (NULL owner) and an owner tag on the card.

src/pages/gpu-service/templates/forms/basic.tsx

@@ -1,4 +1,6 @@
+import PluginExtraFields from '@/components/plugin-extra-fields';
 import { validateLabelNameRegxFor63 } from '@/config';
+import { PageActionType } from '@/config/types';
 import {
   Input as CInput,
   InputNumber,
@@ -28,12 +30,14 @@ export interface BasicResourceMax {
 
 interface BasicProps {
   page?: 'template' | 'instance';
+  action?: PageActionType;
   disabled?: boolean;
   onceMaxRequest?: BasicResourceMax;
 }
 
 const Basic: React.FC<BasicProps> = ({
   page = 'template',
+  action,
   onceMaxRequest,
   disabled
 }) => {
@@ -105,6 +109,10 @@ const Basic: React.FC<BasicProps> = ({
               maxLength={63}
             />
           </Form.Item>
+          <PluginExtraFields
+            name="CreateOrgScopeField"
+            context={{ action, allowGlobal: true }}
+          />
           <Form.Item<FormData>
             name="manufacturer"
             rules={[